The Zvezda T-34/76 is by far a more accurate kit than the Tamiya T-34/76. Tamiya had to develop their kit to accept their motorized gearbox and batteries. Some details had to be beefed up to survive being handled when the hull was opened to change batteries.
Having said that, the Zvezda kit is not as well engineered as the Tamiya kit. The Tamiya kit goes together easily without fit problems. As Stik says, the stiff Zvezda 2-piece vinyl tracks are not ideal; T-34 tracks have a pronounced sag to them; hard to do with stiff vinyl.
If it was my hard earned money, I'd search for one of the numerous Dragon T-34/76 kits out there. I own just about every one, half of them are built. A cursory search on eBay turned up quite a number of them under $20.
AFV Club makes a nice one too; I just got the clear one with interior a while back.
If you search eBay and see the Italeri kit, in 1/35 it is the Zvezda kit and in 1/72 it is the old Esci kit. The Eastern Express/Maquette kits are quite rough/primitive/flash filled, but otherwise accurate.
My apologies if my advice is unwanted and considered rivet counting. I will delete it if anyone finds it offensive and feels it belongs in the trash. In order to appeal to the wide variety of modelers, I will just tell you to buy the one you want and build it out of box and have fun.
This guy on M-L has both the Tamiya and Dragon T-34 kits for sale. It would never hurt to make him an offer less than what you'd pay at the online shop. He might accept it and you save some money.
http://www.network54.com/Forum/47214/thread/1406260937/FS-+1-35+Armor+%2B+accessories